adjacency matrix

Any suggestions as to why this program only reads in the data and doesn't out out it. I have looked at it till I can't see and I think that is my problem. Any suggestions as to where to look or how to fix would be awesome!!

I think this program is self explained.
Read in adjacency matrix, call up a power of it, print it out!!

Code:

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//  Adjacency Matrix
#include <iostream>
using namespace std;

void matin ( int G[][5], int P[][5], int r, int c ){
        int i,j;
        cout << "Enter an edge as 1 and no edge as 0 " << endl
                                << "Please enter matrix by row. " << endl;
        for ( i=0; i< r; i++ ){
                       
                for ( j=0; j<c; j++ ){               
                        cin >> G[i][j];
                        G[i][j] =  P[i][j] ;
                };
        };
}

void matout (int P[][5], int r, int c){
        cout << endl;
        int i,j;
        for ( i=0; i<r; i++ ){
                for ( j=0; j<c; j++ ){
                        cout << P[i][j] << "  ";
                };
                cout << endl;
        };
}

void matmult ( int A[][5], int P[][5], int G[][5], int r, int c, int n){
        int i,j,k;
        for ( k=0; k<r; k++ ){
                        for( i=0; i<r; i++ ){
                                int sum =0;
                                for ( j=0; j<n; j++ ){                                       
                                        sum = sum +  P[k][j]* A[j][i] ;       
                                G[k][i] = sum;       
                                };                       
                        };
        };matout (G,r,c);
}

int matpower ( int A[][5], int P[][5],int r, int c, int n ){
        int G[5][5];
        if ( n == 0 ){              //base case
                cout << "Matrix to the 0 power has ended program " << endl;               
                return 1;
        }       
        else if ( n > 0,--n ){       
                        matmult( A,P,G,r,c, n );
                        matpower ( A,G,r,c,n );//p to g
        };
return 1;
}

int main (){
        int r, c;
        cout << "This matrix program will handle any matrix up to 20 rows and 20 columns" << endl
                << "Please enter size of matrix rows and columns "  << endl;
        cin >> r >> c;       
        int P[5][5];
        int A[5][5];
        if (r!= 0 && c!= 0){
        matin (A,P, r, c);
        cout << endl;
        matout(P, r,c);
        int n;
        cout << "Please enter the power multiple for matrix. " << endl
                <<  "(note: every power up to the one entered will be printed) ";
        cin >> n;
        cout  << endl<< "Matrix from power of 1 through " << n << " power are:"
                << endl;
        matout (P, r, c);
        matpower(P, A, r, c, n);
        }
        return 0;
}
/*
Matrix from power of 1 through 3 power are:

0  1  0  0  1
0  0  1  0  0
0  1  0  0  1
0  0  1  0  0
1  0  0  1  0

1  0  1  1  0
0  1  0  0  1
1  0  1  1  0
0  1  0  0  1
0  1  1  0  1

0  2  1  0  2
1  0  1  1  0
0  2  1  0  2
1  0  1  1  0
1  1  1  1  1
Press any key to continue
*/

---

Code:

---

  ...
  for ( j=0; j<c; j++ ){               
      cin >> G[i][j];
      G[i][j] =  P[i][j] ;
  };
  ...

---

You are overwriting what you just input. You've been staring at the monitor for too long :).

gg

I guess that is what I get for spending Spring Break at home =)
So I am thinking with what little brain I have left that in my matin function I need some sort of loop that will keep advancing me through the matrix?? Doesn't the for loops advance me to the "next space" within the matrix??

>Doesn't the for loops advance me to the "next space" within the matrix??

yes, but you overwrite what you read in...

Code:

---


  ...
  for ( j=0; j<c; j++ ){               
      cin >> G[i][j] ;
      G[i][j] =  P[i][j] ; // should be P[i][j] = G[i][j] ?
  };
  ...

---

Ah ha!! You are right I must get away from this darn computer. Thanks a bunch!!